1. Field of the Invention
The present invention relates generally to devices for cutting a desired formation into a workpiece, and more particularly, to a device for cutting a countersink into a workpiece.
2. Description of the Prior Art
Devices for cutting a countersink into a workpiece are well known in the machining arts. The following U.S. patents are representative of devices employed in cutting countersinks: U.S. Pat. Nos. 3,439,566; 4,032,251; 4,897,000; 4,950,109; and 5,066,172. All of the above-cited patents have one common characteristic. The rotating countersink cutting tool and the means for rotating the countersink cutting tool rotate around the same longitudinal axis.
There are workpieces, however, for which having both the rotating countersink cutting tool and the means for rotating the countersink cutting tool on the same longitudinal axis would make it difficult, if not impossible, to cut a countersink in the workpiece. Such a workpiece may be bulky and have desired countersink locations distributed in a manner such that a desired location for a countersink cannot be placed under the rotating means for driving the countersink tool. In this respect, it would be desirable if a countersink cutting device were provided that which did not require the countersink tool to rotate around the same longitudinal axis that the countersink tool driving device rotates around. Stated somewhat differently, it would be desirable if a countersink cutting device were provided that included a countersink tool that rotates around a longitudinal axis that is offset from the longitudinal axis that the countersink driving tool rotates around.
For precision cutting and for best cutting control, it is desirable that the vertical distance between the countersink driving tool and the countersink cutting tool be kept to a minimum. In this respect, it would be desirable if an offset countersink cutting device were provided in which the vertical distance between the countersink driving tool and the countersink cutting tool is relatively small.
With a conventional countersink cutting device, it is important that the countersink driving tool and the countersink cutting tool be kept in proper alignment. The same can be said for an offset countersink cutting device. In this respect, it would be desirable if an offset countersink cutting device were provided that included provisions for maintaining proper alignment between the countersink driving tool and the offset countersink cutting tool.
When a workpiece is subjected to the rotational cutting of a rotating countersink cutting tool, there is an interplay of forces, and there is a tendency to destabilize the alignment between the countersink driving tool, the countersink cutting tool, and the workpiece. The tendency to destabilize the alignment between the countersink driving tool, the countersink cutting tool, and the workpiece may be aggravated when the countersink cutting tool and the workpiece are offset from the countersink driving tool. In this respect, it would be desirable if an offset countersink cutting device were provided that had provisions for stabilizing the alignment between the countersink driving tool, the countersink cutting tool, and the workpiece.
Workpieces vary quite a bit as to their respective sizes and their respective countersink requirements. In this respect, an offset countersink device that has an unchangeable offset setting may, at times, be undesirably limiting. In this respect, it would be desirable if an offset countersink cutting device were provided that had an adjustable offset.
After a certain amount of use, a countersink cutting tool will wear out. As such, it must be replaced. In this respect, it would be desirable if an offset countersink cutting device were provided that had an easily replaced countersink cutting tool.
Thus, while the foregoing body of prior art indicates it to be well known to use devices for cutting countersinks in a workpiece, the prior art described above does not teach or suggest a offset drive countersink apparatus which has the following combination of desirable features: (1) does not require the countersink tool to rotate around the same longitudinal axis that the countersink tool driving device rotates around; (2) includes a countersink tool that rotates around a longitudinal axis that is offset from the longitudinal axis that the countersink driving tool rotates around; (3) includes a countersink apparatus in which the vertical distance between the countersink driving tool and the countersink cutting tool is relatively small; (4) includes provisions for maintaining proper alignment between the countersink driving tool and the offset countersink cutting tool; (5) has provisions for stabilizing the alignment between the countersink driving tool, the countersink cutting tool, and the workpiece; (6) provides an offset countersink cutting device that has an adjustable offset; and (7) provides an offset countersink cutting device that has an easily replaced countersink cutting tool. The foregoing desired characteristics are provided by the unique offset drive countersink apparatus of the present invention as will be made apparent from the following description thereof. Other advantages of the present invention over the prior art also will be rendered evident.